fix typos

Author: coke

doc/Type/Date.pod6

@@ -254,11 +254,10 @@ when the process has been awakened by some external event (e.g., Virtual Machine
 or Operating System events).
 Under normal condition, when sleep is not interrupted, the returned C<Duration>
 has a value of C<0>, meaning no extra seconds remained to sleep.
-Therfore, in normal situations:
+Therefore, in normal situations:
 
     say sleep-timer 3.14;  # OUTPUT: «0␤»
 
-
 The same result applies to edge cases, when a negative or zero time to sleep
 is passed as argument:
 
@@ -276,7 +275,7 @@ See also L<sleep-until|/routine/sleep-until>.
 Works similar to C<sleep> but checks the current time and keeps sleeping
 until the required instant in the future has been reached.
 It uses internally the C<sleep-timer> method in a loop to ensure that,
-if accidentaly woken up early, it will wait again for the specified
+if accidentally woken up early, it will wait again for the specified
 amount of time remaining to reach the specified instant.
 goes back to sleep